Add --amend and --squash options to bdep-release

7 files changed, 365 insertions, 25 deletions

diff --git a/bdep/git.cxx b/bdep/git.cxx
index 91964aa..9509275 100644
--- a/bdep/git.cxx
+++ b/bdep/git.cxx
@@ -45,7 +45,7 @@ namespace bdep
   }
 
   optional<string>
-  git_line (process&& pr, fdpipe&& pipe, bool ie)
+  git_line (process&& pr, fdpipe&& pipe, bool ie, char delim)
   {
     optional<string> r;
 
@@ -56,7 +56,7 @@ namespace bdep
       ifdstream is (move (pipe.in), fdstream_mode::skip, ifdstream::badbit);
 
       string l;
-      if (!eof (getline (is, l)))
+      if (!eof (getline (is, l, delim)))
         r = move (l);
 
       is.close (); // Detect errors.
diff --git a/bdep/git.hxx b/bdep/git.hxx
index e699947..c674926 100644
--- a/bdep/git.hxx
+++ b/bdep/git.hxx
@@ -31,6 +31,19 @@ namespace bdep
              I&& in, O&& out, E&& err,
              A&&... args);
 
+  template <typename I, typename O, typename E, typename... A>
+  inline process
+  start_git (const semantic_version& min_ver,
+             dir_path& repo,
+             I&& in, O&& out, E&& err,
+             A&&... args)
+  {
+    return start_git (min_ver,
+                      const_cast<const dir_path&> (repo),
+                      forward<I> (in), forward<O> (out), forward<E> (err),
+                      forward<A> (args)...);
+  }
+
   // Wait for git process to terminate.
   //
   void
@@ -70,7 +83,23 @@ namespace bdep
   // redirected output pipe.
   //
   optional<string>
-  git_line (process&& pr, fdpipe&& pipe, bool ignore_error);
+  git_line (process&&, fdpipe&&, bool ignore_error, char delim = '\n');
+
+  // Similar to git_line() functions but return the complete git output.
+  //
+  template <typename... A>
+  optional<string>
+  git_string (const semantic_version&, bool ignore_error, A&&... args);
+
+  template <typename... A>
+  optional<string>
+  git_string (const semantic_version&,
+              const dir_path& repo,
+              bool ignore_error,
+              A&&... args);
+
+  optional<string>
+  git_string (process&&, fdpipe&&, bool ignore_error);
 
   // Try to derive a remote HTTPS repository URL from the optionally specified
   // custom git config value falling back to remote.origin.build2Url and then
diff --git a/bdep/git.ixx b/bdep/git.ixx
index dbc43cb..f06a000 100644
--- a/bdep/git.ixx
+++ b/bdep/git.ixx
@@ -35,4 +35,23 @@ namespace bdep
                      "-C", repo,
                      forward<A> (args)...);
   }
+
+  template <typename... A>
+  inline optional<string>
+  git_string (const semantic_version& min_ver,
+              const dir_path& repo,
+              bool ie,
+              A&&... args)
+  {
+    return git_string (min_ver,
+                       ie,
+                       "-C", repo,
+                       forward<A> (args)...);
+  }
+
+  inline optional<string>
+  git_string (process&& pr, fdpipe&& pipe, bool ignore_error)
+  {
+    return git_line (move (pr), move (pipe), ignore_error, '\0' /* delim */);
+  }
 }
diff --git a/bdep/git.txx b/bdep/git.txx
index 5ff5e6c..f3bedf0 100644
--- a/bdep/git.txx
+++ b/bdep/git.txx
@@ -89,7 +89,7 @@ namespace bdep
 
   template <typename... A>
   optional<string>
-  git_line (const semantic_version& min_ver, bool ie, A&&... args)
+  git_line (const semantic_version& min_ver, bool ie, char delim, A&&... args)
   {
     fdpipe pipe (open_pipe ());
     auto_fd null (ie ? open_dev_null () : auto_fd ());
@@ -100,7 +100,21 @@ namespace bdep
                            ie ? null.get () : 2 /* stderr */,
                            forward<A> (args)...));
 
-    return git_line (move (pr), move (pipe), ie);
+    return git_line (move (pr), move (pipe), ie, delim);
+  }
+
+  template <typename... A>
+  inline optional<string>
+  git_line (const semantic_version& min_ver, bool ie, A&&... args)
+  {
+    return git_line (min_ver, ie, '\n' /* delim */, forward<A> (args)...);
+  }
+
+  template <typename... A>
+  inline optional<string>
+  git_string (const semantic_version& min_ver, bool ie, A&&... args)
+  {
+    return git_line (min_ver, ie, '\0' /* delim */, forward<A> (args)...);
   }
 
   template <typename... A>
diff --git a/bdep/release.cli b/bdep/release.cli
index 2dadb7f..768cba1 100644
--- a/bdep/release.cli
+++ b/bdep/release.cli
@@ -44,11 +44,16 @@ namespace bdep
      package's \cb{manifest} file, commits these changes (unless
      \cb{--no-commit} is specified), tags this commit (unless \cb{--no-tag} is
      specified), and, if \cb{--push} is specified, pushes the changes to the
-     remote. Note that in this case the project's repository index is expected
-     to already contain other changes since for a revision all the associated
-     changes, including to version, must belong to a single commit. In this
-     mode \cb{release} will also silently replace an existing tag for the same
-     version.
+     remote. Note that in this mode \cb{release} will also silently replace an
+     existing tag for the same version.
+
+     When releasing a revision, the project's repository index is expected to
+     already contain other changes since for a revision all the associated
+     changes, including to version, must belong to a single commit.
+     Alternatively, a revision can be released by amending one or more
+     existing commits using the \cb{--amend} and \cb{--squash} options. In
+     this case the index may still contain additional changes but is not
+     required to.
 
      The \cb{release} command also has a number of \i{continue modes} that
      allow the completion of steps that were previously suppressed with the
@@ -123,6 +128,20 @@ namespace bdep
       "Open the next development cycle instead of releasing a new version."
     }
 
+    bool --amend
+    {
+      "Release a revision by amending the latest commit instead of making
+       a new one."
+    }
+
+    size_t --squash = 1
+    {
+      "<num>",
+      "Release a revision by squashing the specified number of previous
+       commits and then amending the result. Requires the \cb{--amend}
+       option to be specified."
+    }
+
     bool --alpha
     {
       "Release an alpha instead of the final version."
diff --git a/bdep/release.cxx b/bdep/release.cxx
index c6eef28..71c6372 100644
--- a/bdep/release.cxx
+++ b/bdep/release.cxx
@@ -393,10 +393,12 @@ namespace bdep
     // Note: the use-case for forcing would be to create a commit to be
     // squashed later.
     //
-    // Also, don't complain if we are not committing.
+    // Also, don't complain if we are not committing or amending an existing
+    // commit.
     //
     if (!st.staged      &&
         !o.no_commit () &&
+        !o.amend ()     &&
         o.force ().find ("unchanged") == o.force ().end ())
       fail << "project directory has no staged changes" <<
         info << "revision increment must be committed together with "
@@ -458,6 +460,16 @@ namespace bdep
         }
       };
 
+      // Verify that an option is specified only if it's prerequisite option
+      // is also specified.
+      //
+      auto require = [] (const char* opt,    bool opt_specified,
+                         const char* prereq, bool prereq_specified)
+      {
+        if (opt_specified && !prereq_specified)
+          fail << opt << " requires " << prereq;
+      };
+
       // Check the mode options.
       //
       verify ("--revision", o.revision ());
@@ -519,6 +531,20 @@ namespace bdep
       verify ("--push",      o.push ());
       verify ("--show-push", o.show_push ());
       verify ("--no-commit", o.no_commit ()); // Not for tagging (see above).
+
+      // Verify the --amend and --squash options.
+      //
+      require ("--amend", o.amend (), "--revision", o.revision ());
+      require ("--squash", o.squash_specified (), "--amend", o.amend ());
+
+      if (o.squash_specified () && o.squash () == 0)
+        fail << "invalid --squash value: " << o.squash ();
+
+      // There is no sense to amend without committing.
+      //
+      gopt = nullptr;
+      verify ("--amend",     o.amend ());     // Revising only (see above).
+      verify ("--no-commit", o.no_commit ()); // Not for tagging (see above).
     }
 
     // Fully parse package manifest verifying it is valid and returning the
@@ -774,22 +800,56 @@ namespace bdep
         return 1;
     }
 
-    // Stage and commit the project changes. Open the commit message in the
-    // editor if requested and --no-edit is not specified or if --edit is
-    // specified.
+    // Stage the project changes and either commit them separately or amend
+    // the latest commit. Open the commit messages in the editor if requested
+    // and --no-edit is not specified or if --edit is specified. Fail if the
+    // process terminated abnormally or with a non-zero status, unless
+    // return_error is true in which case return the git process exit
+    // information.
     //
-    auto commit_project = [&o, &prj] (const string& msg, bool edit)
+    auto commit_project = [&o, &prj] (const strings& msgs,
+                                      bool edit,
+                                      bool amend = false,
+                                      bool return_error = false)
     {
+      assert (!msgs.empty ());
+
+      cstrings msg_ops;
+      for (const string& m: msgs)
+      {
+        msg_ops.push_back ("-m");
+        msg_ops.push_back (m.c_str ());
+      }
+
       // We shouldn't have any untracked files or unstaged changes other than
       // our modifications, so -a is good enough.
       //
-      run_git (git_ver,
-               prj.path,
-               "commit",
-               verb < 1 ? "-q" : verb >= 2 ? "-v" : nullptr,
-               "-a",
-               (edit && !o.no_edit ()) || o.edit () ? "-e" : nullptr,
-               "-m", msg);
+      // We don't want git to print anything to stdout, so let's redirect it
+      // to stderr for good measure, as git is known to print some
+      // informational messages to stdout.
+      //
+      process pr (
+        start_git (git_ver,
+                   prj.path,
+                   0 /* stdin  */,
+                   2 /* stdout */,
+                   2 /* stderr */,
+                   "commit",
+                   verb < 1 ? "-q" : verb >= 2 ? "-v" : nullptr,
+                   amend ? "--amend" : nullptr,
+                   "-a",
+                   (edit && !o.no_edit ()) || o.edit () ? "-e" : nullptr,
+                   msg_ops));
+
+      // Wait for the process termination.
+      //
+      if (return_error)
+        pr.wait ();
+      else
+        finish_git (pr); // Fails on process error.
+
+      assert (pr.exit);
+      return move (*pr.exit);
     };
 
     // Release.
@@ -863,7 +923,82 @@ namespace bdep
       else
         m = "Release version " + pkg.release_version->string ();
 
-      commit_project (m, st.staged);
+      strings msgs ({move (m)});
+
+      if (o.amend ())
+      {
+        // Collect the amended/squashed commit messages.
+        //
+        // This would fail if we try to squash initial commit. However, that
+        // shouldn't be a problem since that would mean squashing the commit
+        // for the first release that we are now revising, which is
+        // meaningless.
+        //
+        optional<string> ms (
+          git_string (git_ver,
+                      prj.path,
+                      false /* ignore_error */,
+                      "log",
+                      "--format=%B",
+                      "HEAD~" + to_string (o.squash ()) + "..HEAD"));
+
+        if (!ms)
+          fail << "unable to obtain commit messages for " << o.squash ()
+               << " latest commit(s)";
+
+        msgs.push_back (move (*ms));
+      }
+
+      // Note that we could handle the latest commit amendment (squash == 1)
+      // here as well, but let's do it via the git-commit --amend option to
+      // revert automatically in case of git terminating due to SIGINT, etc.
+      //
+      if (o.squash () > 1)
+      {
+        // Squash commits, reverting them into the index.
+        //
+        run_git (git_ver,
+                 prj.path,
+                 "reset",
+                  verb < 1 ? "-q" : nullptr,
+                 "--soft",
+                 "HEAD~" + to_string (o.squash ()));
+
+        // Commit editing the message.
+        //
+        process_exit e (commit_project (msgs,
+                                        true  /* edit */,
+                                        false /* amend */,
+                                        true  /* ignore_error */));
+
+        // If git-commit terminated normally with non-zero status, for example
+        // due to the empty commit message, then revert the above reset and
+        // fail afterwards. If it terminated abnormally, we probably shouldn't
+        // mess with it and leave things to the user to handle.
+        //
+        if (!e)
+        {
+          if (e.normal ())
+          {
+            run_git (git_ver,
+                     prj.path,
+                     "reset",
+                     verb < 1 ? "-q" : nullptr,
+                     "--soft",
+                     "HEAD@{1}"); // Previously checked out revision.
+
+            throw failed (); // Assume the child issued diagnostics.
+          }
+
+          fail << "git " << e;
+        }
+      }
+      else
+      {
+        // Commit or amend.
+        //
+        commit_project (msgs, st.staged || o.amend () /* edit */, o.amend ());
+      }
 
       // The (possibly) staged changes are now committed.
       //
@@ -932,7 +1067,7 @@ namespace bdep
 
       // Commit the manifest rewrites.
       //
-      commit_project ("Change version to " + ov, st.staged);
+      commit_project ({"Change version to " + ov}, st.staged);
     }
 
     if (push)
diff --git a/tests/release.testscript b/tests/release.testscript
index 2f63265..1ba4cbc 100644
--- a/tests/release.testscript
+++ b/tests/release.testscript
@@ -651,6 +651,124 @@ log2   = $gp2 log '--pretty=format:"%d %s"'
          Create
         EOO
     }
+
+    : amend
+    :
+    {
+      test.arguments += --push --amend --no-edit
+
+      +$clone_repos
+
+      +echo '' >+ prj/repositories.manifest
+      +$gp commit -a -m 'Fix repositories.manifest'
+
+      +echo '' >+ prj/buildfile
+      +$gp commit -a -m 'Fix buildfile' -m "Add '\n' to the end of the file."
+
+      +echo '' >+ prj/manifest
+      +$gp add manifest
+
+      : no-squash
+      :
+      {
+        $clone_repos;
+
+        $* 2>>~%EOE%;
+          %Updated tag 'v0.1.0' \(was \.*\)%d
+          EOE
+
+        $clone2;
+        $log2 >>:~%EOO%;
+          % \(HEAD -> master, tag: v0.1.0, \.*\) Release version 0.1.0\+1%d
+           Fix repositories.manifest
+           Release version 0.1.0
+           Create
+          EOO
+
+        $log2 '--pretty=format:%B' >>EOO
+          Release version 0.1.0+1
+
+          Fix buildfile
+
+          Add 'n' to the end of the file.
+
+          Fix repositories.manifest
+
+          Release version 0.1.0
+
+          Create
+          EOO
+      }
+
+      : squash
+      :
+      {
+        $clone_repos;
+
+        $* --squash 2 2>>~%EOE%;
+          %Updated tag 'v0.1.0' \(was \.*\)%d
+          EOE
+
+        $clone2;
+        $log2 >>:~%EOO%;
+          % \(HEAD -> master, tag: v0.1.0, \.*\) Release version 0.1.0\+1%d
+           Release version 0.1.0
+           Create
+          EOO
+
+        $log2 '--pretty=format:%B' >>EOO
+          Release version 0.1.0+1
+
+          Fix buildfile
+
+          Add 'n' to the end of the file.
+
+          Fix repositories.manifest
+
+          Release version 0.1.0
+
+          Create
+          EOO
+      }
+
+      : no-changes-staged
+      :
+      {
+        $clone_repos;
+
+        $gp commit -a -m 'Change manifest';
+
+        $* 2>>~%EOE%;
+          %Updated tag 'v0.1.0' \(was \.*\)%d
+          EOE
+
+        $clone2;
+        $log2 >>:~%EOO%;
+          % \(HEAD -> master, tag: v0.1.0, \.*\) Release version 0.1.0\+1%d
+           Fix buildfile
+           Fix repositories.manifest
+           Release version 0.1.0
+           Create
+          EOO
+
+
+        $log2 '--pretty=format:%B' >>EOO
+          Release version 0.1.0+1
+
+          Change manifest
+
+          Fix buildfile
+
+          Add 'n' to the end of the file.
+
+          Fix repositories.manifest
+
+          Release version 0.1.0
+
+          Create
+          EOO
+      }
+    }
   }
 
   : open
@@ -1016,5 +1134,11 @@ log2   = $gp2 log '--pretty=format:"%d %s"'
   $* --push     --show-push 2>'error: both --push and --show-push specified'     != 0;
   $* --edit     --no-commit 2>'error: both --no-commit and --edit specified'     != 0;
 
-  $* --open-base 1.2.3 --open-beta 2>'error: both --open-beta and --open-base specified' != 0
+  $* --open-base 1.2.3 --open-beta 2>'error: both --open-beta and --open-base specified' != 0;
+
+  $* --amend                        2>'error: --amend requires --revision'            != 0;
+  $* --squash 1                     2>'error: --squash requires --amend'              != 0;
+  $* --revision --amend --squash 0  2>'error: invalid --squash value: 0'              != 0;
+  $* --revision --amend --no-commit 2>'error: both --amend and --no-commit specified' != 0
+
 }